Acer×freemani named `DTR 102`

ABSTRACT

This new variety of Acer×freemani was discovered in Urbana, Ill.; it shares some of the characteristics of both parent trees Acer rubrum and Acer saccharinum is a dense crown, heavy leaf population, substantial limb scaffold, rapid rate of growth, resistance to drought and winter crown damage, and a brilliant red fall color each October on all parts of the leaves on all ages of trees.

BACKGROUND OF THE INVENTION

This variety of Acer×freemani was discovered by the applicant growing ina yard of a private residence in Urbana, Ill. The new variety exhibits afast growth habit producing a broadly ovate crown with a heavy leafpopulation carried on a substantial limb scaffold. Further, this tree,through the years, has shown the ability to withstand drought andadverse environmental conditions, and exhibits no crown damage orbreakage due to excessive snow loads normally periodically experiencedin the central Midwest. Also, it has shown the ability to produce abright crimson leaf color in October of each season, coloringsimultaneously and producing this color on trees of all sizes. I haveproduced 200 trees in my nursery in Oquawka, Ill. by chip budding,obtaining buds from the parent tree; all progeny exhibited thecharacteristics of the parent tree.

SUMMARY OF THE INVENTION

This selection of Acer×freemani shares some of the characteristics ofboth parent trees (Acer rubrum and Acer saccharinum) responding withrapid growth, a broadly ovate crown, dense leaf population, intermediateterminal growth coloration, drought resistance and tolerance of adverseenvironmental conditions of its Acer saccharinum and simultaneousparentage.

Major scaffold branches are strongly ascending with crotch angles ofapproximately 20 degrees, compared with crotch angles of 45 to 60degrees on silver maple and 45 to 55 degrees on red maple of same ageand growing under similar culture; my new tree does not exhibitsusceptibility to crown damage or any breakage due to excessive snowloads that are normally periodically experienced in central Illinois,reflecting a branch joint union of greater strength than the parentspecies, Acer saccharinum. Nursery liners produced by chip buds obtainedfrom the parent tree maintain the approximately 20 degree crotch angleand the substantial limb scaffold more like the Acer rubrum parentspecies, but exhibit a hybrid vigor with five-years-old trees showing anaverage terminal growth of 45.6 inches, compared to an average of 24.3inches of terminal growth on red maple of same age and growing withsimilar culture in my nursery in Oquawka, Ill. This vigor, coupled withthe ascending branching and branch density, produces a distinctive treewith a controlled yet well-branched crown at an early age. Further, thisterminal growth can be identified by an intermediate coloration thatmost closely corresponds to 176A of the R.H.S. Colour Chart, The RoyalHorticultural Society, London, England, as compared to the terminalgrowth color of the parent species, Acer rubrum (R.H.S. 183A), and tothe terminal growth color of the parent species, Acer saccharinum(R.H.S. 172A). Also, branch collars on my new variety display adistinctive greyed-orange coloration (R.H.S. 165D), this colorationbeing absent on red maples and silver maples of same age growing withsimilar culture. October color on trees of all ages turns a persistantintense ruby red on trees of all sizes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: Is a photographic view of my new variety as it appears inOctober showing overall bright crimson leaf color.

FIG. 2: Is a photographic view of my new variety as it appears inmid-summer.

FIG. 3: Is a photographic view of some individual leaves as they fallfrom the tree in early November, 1988.

FIG. 4: Is a photographic view showing the heavy leaf population andsubstantial limb scaffold and vigorous growth of two-years-old trees inthe nursery.

FIG. 5: Is a photographic view showing the tree in dormant condition.

DESCRIPTION OF THE NEW PLANT

The following is a detailed description of my new variety ofAcer×freemani, the stated observations having been made on trees inUrbana, Ill. and Oquawka, Ill. by the applicant and found to distinguishfrom the species.

Origin: A tree of unknown origin, a hybrid between red maple (Acerrubrum) and silver maple (Acer saccharinum) found in a yard of a privateresidence in Urbana, Ill.

Classification: Acer×freemani.

Parentage: A sport of red maple (Acer rubrum) and silver maple (Acersaccharinum).

Form: Broadly ovate.

Habit: A deciduous tree with a short single trunk, a central but notdominant leader and numerous, strongly ascending main and secondarybranches, with none descending, and the branching habit appearingintermediate of the two parent species, but with a higher density ofbranching than normally seen in either parent species; crown broadlyovate in shape, symmetrical and dense; major scaffold branches arestrongly ascending with crotch angles of approximately 20 degrees; rapidgrowth and drought tolerance of silver maple but not exhibiting crownbreakage or damage due to excessive snow loads. Mature tree height of 74feet and a crown spread of 54 feet, most closely resembling the parentAcer saccharinum in ultimate size. Juvenile trees produced from chipbuds obtained from the parent tree maintain the higher density ofbranches and the approximate 20 degree crotch angle, growing vigorouslyas expressed in inches of terminal growth, the average being 45.6 inchesper year.

Twigs: Moderately stout, 2.5-4 mm in diameter, glabrous,orange-reddish-brown (R.H.S. 176A), lustrous, marked with tan,hyaline-margined, elliptic lenticels, with a slight disagreeable odorwhen crushed; outermost twigs curved upwards. Leaf scars opposite,C-shaped, connected by a fine line, with 3 bundle traces, stipule scarslacking.

Winter buds: Two types are present. Vegetative buds 3.5-5 mm long,rounded at tips, laterally flattened, sessile, bright purple-red (R.H.S.183B), glabrous, with 2 pairs of exposed, blunt, ciliate scales. Flowerbuds 3-4 mm in diameter, globose, very shortly stalked, bright to darkred-purple (R.H.S. 182A), some with adpressed orange hairs, with 2-4pairs of exposed bud scales, forming whorled clusters around the twigs.

Bark: Smooth, thin and medium grey on branches and juvenile trees, likea red maple but differing in color in that the selection corresponds toR.H.S. 201C with brown-grey undertones most nearly resembling R.H.S.199A. Branch scars on juvenile trees a greyed-orange color (R.H.S.165D). Bark on the trunk of the mature tree is darker than its branches(R.H.S. 198A), with large, flat, thin scales that peel away at thebottom, like a silver maple.

Leaves: Oppositely arranged, deciduous, simple, resembling those of asilver maple; blades palmately and deeply 3-5 lobed, 7-10 cm long and7-12 cm wide, the tips long acuminate, the margins coarselydouble-serrate, the bases rounded-truncate to shallowly cordate; leafsurface lustrous green above like a red maple (R.H.S. 137A), silverybelow like a silver maple (R.H.S. 147B); petioles slender, flattened,2.5-9 cm long, most nearly resembling the silver maple parentage.

Flowers: Nearly sessile, the pedicels 1-2 mm long; calyx cup 1.5 mmlong; petals absent; ovary pubescent with long trichomes, the stypes 5mm long. The dates of flowering not noted, flowering observed at theusual time of early April in central Illinois.

Fruit: Schizocarps splitting apart into two samaras, the sinus betweenthe samaras V-shaped; each mericarp 4-5 cm long. Date of seed fail hasnot been recorded. The fertility of the seed is not known.

Fall color: Has the red color of a red maple with all parts of allleaves on all aged trees turning a uniform red color most closelyresembling R.H.S. 60B. The young trees also have a similar red fallcolor.

I claim:
 1. A new and distinctive variety of Acer×freemani named `DTR102`, as described and illustrated herein, that differs from all othervarieties by the unique combination of characteristics intermediatebetween red and silver maples with (1) simultaneous red fall color onall leaves of all ages of trees; (2) broadly ovate crown, short trunk,central but not dominant leader, and numerous ascending main branches;and (3) drought resistance and rapid growth of silver maple without thesusceptibility to crown damage or breakage due to excessive snow loads.